For the second straight year, we’ll spend the summer counting down the top 20 players on the Detroit Lions' roster in anticipation of training camp.

This isn’t meant to be a gauge of how players have performed in the past or what they did last year. This is more a prediction of how valuable each player will be to the Lions this fall, accounting for the role they’ll play on the team. Left tackle Taylor Decker would have been a top-five selection had he not torn the labrum in his right shoulder in early June. With Decker potentially out for half the season or more, his role has diminished to the point he does not appear on this list.

No. 8: Theo Riddick

Contract status: Signed a 3-year extension last summer that keeps him under contract through 2019.

Why he’s No. 8: There were a number of reasons the Lions struggled offensively late last season. The competition they faced, Matthew Stafford’s bum finger, and the fact that Riddick wasn’t on the field. Riddick missed the final four games of the regular season last year with wrist injuries that eventually required surgery. He still finished as the team’s leading rusher and ranked fifth in receptions, and he should be in for an even better season – assuming he’s healthy – in 2017. Riddick did not practice with the Lions this spring as he rehabbed from double wrist surgery, but he’s one of the three best pass-catching backs in the NFL and will play a significant role on offense.

2017 projection: Four years into his career, Riddick still looks like a slot receiver playing the running back position. That’s not to demean his skill set. He’s a dynamic playmaker in the open field and gives the Lions a backfield weapon few teams can match. But playing behind Ameer Abdullah, Riddick’s biggest contributions this fall will once again come in the passing game. As long as health isn’t an issue, Riddick should approach 1,000 yards from scrimmage, with 700 or so of it as a receiver.